install_base_ubuntu.sh: Revamp and fix the Android SDK download

* General cleanup to clarify the flow of the script in the different scenarios
* Add --install-all option to have future-proof infrastructure using LISA
* Support Archlinux (pacman and package list)
* Rename to generic name install_base.sh

* Download a far smaller archive containing only the necessary tools rather than
  the whole SDK
* Rename --install-android-sdk into --install-android-platform-tools, since that
  is now what it is doing